Wednesday November 6, 2013, 3:35 pm
There are some snakes around already that are the size of horses - anacondas and some pythons in Florida. Interesting and a bit creepy to ponder what changes climate shifts might bring. Thanks for posting Carrie

Wednesday November 6, 2013, 5:41 pm
The "visit site" link doesn't want to reveal the page - - - BUT - My immediate sense from the header is"Yep - and the first place it is showing up is among our pols - - -"
I, too, love snakes - Believe my fa gave me (briefly, and under TOTAL supervision) my first snake at age 4, a little green racer. I went on to a lifetime interest - - -MO never quite recovered

Wednesday November 6, 2013, 5:49 pm
TEXT OF ARTICLE:
Tens of millions of years ago, snakes were as big as horses. Horses were almost as small as snakes. And in a warmer world, it could get that way again.

That's the implication of research showing that warmer temperatures generally favor smaller mammals and larger reptiles.

"You see the size of these animals dancing with the climate," said Jonathan Bloch, a paleontologist at the Florida Museum of Natural History.

Bloch delved into the connection between body size and global temperatures, particularly during a hot time known as the Paleocene-Eocene Thermal Maximum, on Monday during the ScienceWriters2013 conference here in Gainesville. Like so many facets of global change, the lessons from the distant past don't make the far future look all that sunny. Super-snakes, anyone?

Some like it hot
For years, Bloch and his colleagues have traced the ups and downs of the Paleocene Epoch, which lasted from the downfall of the dinosaurs 65 million years ago to the start of the Eocene about 56 million years ago. One of the key sites for fossils from that age is the Cerrejon Mine in Colombia, where the coal seams are so active they can spontaneously combust.

"It really is like hell, but it's heaven for fossils," Bloch said.

That's where Bloch found evidence of 60 million-year-old turtles as big as breakfast tables, and a snake called Titanoboa that was as long as a bus. Pointing toward the entryway at the back of the hall, Bloch said, "Imagine that the snake would have to squeeze through the door, and come up to your waist."

Snakes, turtles and other reptiles tend to depend on the environment to regulate their heat — putting them in a category known as ectotherms. ("Cold-blooded" is a commonly used term, though it's a bit of a misnomer.) The only way ancient ectotherms could get as big as they did would be for them to live in a hot climate, and the world was indeed much hotter during the Paleocene-Eocene Thermal Maximum.

Experts estimate that global temperatures jumped somewhere in the range of 9 to 14 degrees Fahrenheit (5 to 8 degrees Celsius), due to a massive but mysterious release of greenhouse gases. Titanoboa, for example, thrived amid temperatures as hot as 93 degrees F (34 degrees C).

Mini-mammals
Paleontologists have also studied how mammals fared back in the Paleocene-Eocene. Last year, Bloch and other researchers said the ancestors of modern-day horses shrunk to the size of housecats when temperatures spiked 55 million years ago. This month, a different team reported that another episode of mammalian dwarfism occurred during a second warming event 2 million years later.

"The fact that it happened twice significantly increases our confidence that we're seeing cause and effect, that one interesting response to global warming in the past was a substantial decrease in body size in mammalian species," the University of Michigan's Philip Gingerich, one of the paleontologists behind the latest study, said in a news release.

Several factors have been proposed for the mammalian downsizing: Research suggests that when temperatures rise into the mid-90s (35 degrees C) for an extended period, mammals have a harder time regulating body heat, and less nutrition is available from plant sources. Under those conditions, smaller mammals would fare better than bigger ones.

What lies ahead?
Here's the scary part: If it's happened before, it could happen again — and perhaps sooner than we think. Bloch noted that atmospheric carbon dioxide levels are approaching what they were during the Paleocene-Eocene Thermal Maximum.

"You have to go back tens of millions of years before you get close to or higher than what we're talking about for the next couple of hundred years," Bloch said.

Bloch hinted that he and his colleagues may soon be filling out the picture for the rise of mammals with more fossil finds. In any case, learning more about the hot times of the ancient past — and how they cooled off — could provide the key for coping with future climate change.

Somehow, our planet found a way to reduce atmospheric carbon dioxide and its global warming effect. Perhaps humanity can take advantage of those same strategies — and if so, the record of the Paleocene-Eocene Thermal Maximum and its aftermath could serve as a "user's manual for Earth," Bloch said.

More tales of the first mammals:

Did mammals spread out from an Asian Eden?
Post-dinosaur mammal was fat and slow
Pint-sized primates were first in North America
Update for 9:40 a.m. ET Nov. 6: An earlier version of this story included an embedded YouTube version of the Smithsonian Channel documentary "Titanoboa: Monster Snake." However, that version of the video can only be played back from the original YouTube page. The episode is also available on the Smithsonian Channel website.

Alan Boyle is NBCNews.com's science editor as well as president of the Council for the Advancement of Science Writing. CASW and the National Association of Science Writers presented the ScienceWriters2013 conference in Gainesville, in cooperation with the University of Florida. Bloch's talk was part of CASW's New Horizons in Science briefings.

Wednesday November 6, 2013, 8:09 pm
Fascinating. Snakes are interesting, I like to give their chins a tickle and watch their tongues. When I was younger I would catch a few in the wild, say hello, tickle under their chins, most seem to enjoy that. Then I let them go, some did not seem in much of a hurry to leave. These days I take a photo of them when I see them, or move them off of the rural road if they are sunning themselves there. It might be warm to sunbath on a dirt road but not safe for them to sit in the middle of the road.

Thursday November 7, 2013, 12:50 pm
Pythons here in Fl. because people get them for pets, & then they get too big to handle, DUH, & they turn them loose in the Everglades to endanger all our native animals .

Thursday November 7, 2013, 12:52 pm
I have rat snakes in my backyard habitat, & I love them, but pythons & the like are also hazardous to people's pets.....as some have found out .Cats, dogs, rabbits, other domestic animals & snakes do not mix.

Thursday November 7, 2013, 5:57 pm
Noted and signed. I dislike snakes a lot!!! When the Big Alberta Flood happened in June, there was a young fells living in one of the smaller towns that had been ordered to evacuate, but he did not want to leave, as in his basement it was full of glass cages etc. of all different kind of snakes - of course not native to our country. Can you imagine what would have happened if all these snakes were released into one of our biggest rivers!!!!
Just like in Florida, when people cannot look after the pythons anymore, they just dump they off. Does the SPCA take snakes, I wonder. Thanks for a good article.

Saturday November 9, 2013, 2:32 am
Thanks so much for this fascinating article . I just love this stuff ! I have a burning interest in anthropology & archeology, paleontology. geology, microbiology, and just science in general.....so I love these articles. ...Thanks again. !!!